Generalized growth and approximation errors of entire harmonic functions in \(R^n\), \(n \geq 3\)

In this paper we study the continuation of harmonic functions in the ball to the entire harmonic functions in space \(\mathbb{R}^n\), \(n\geq 3\). The generalized order introduced by M.N. Seremeta has been used to characterize the growth of such functions. Moreover, the generalized order, generalized lower order and generalized type have been characterized in terms of harmonic polynomial approximation errors. Our results apply satisfactorily for slow growth.